Knife rack



FIG. 1 is a front elevation view of a knife rack showing my new design;

FIG. 2 is a rear elevation view thereof;

FIG. 3 is a left side elevation view thereof;

FIG. 4 is a right side elevation view thereof;

FIG. 5 is a top plan view thereof; and,

FIG. 6 is a bottom plan view thereof.

The ornamental design for a knife rack, as shown.